STABILITY OF CATALYSTS IN THE PROCESS OF PHOTOCATALYTIC HYDROGEN PRODUCTION

This study focuses on enhancing the efficiency and stability of catalysts containing molybdenum (Mo) and tungsten (W) in the process of photocatalytic hydrogen production. Their structural, electronic, optical, and catalytic properties were thoroughly investigated. The development of low-cost and active catalysts for green hydrogen production is one of the key challenges in modern energy and environmental science. In this work, MoS₂- and WOx-based catalysts were synthesized via a hydrothermal method and subjected to thermal treatment at various temperatures. Their structural, morphological, and optical characteristics were comprehensively analyzed using advanced techniques such as Raman spectroscopy and UV-Vis. Hydrogen production reactions were carried out using a specially designed solar simulator, and the photocatalytic activity and stability of the catalysts were evaluated. The MoS-A320 sample demonstrated the highest hydrogen evolution activity (83 mL/h·g) and maintained 93% of its initial performance after five cycles, which is comparable to that of platinum-based catalysts. In contrast, WOx-based catalysts showed relatively lower activity. The results revealed that synthesis parameters and thermal treatment conditions have a significant influence on the properties of Mo- and W-based catalysts. This study represents an important step toward the development of efficient, stable, and affordable catalysts for green energy systems and water electrolysis. The findings offer new opportunities for designing cost-effective and high-performance Mo- and W-based catalysts.

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